Application data implementation - Arc protection - Auto synchronization - Bay control and measurement - Merging unit - Transformer protection - 2 winding - Feeder protection - Voltage regulation - Capacitor bank protection - Petersen Coil control - Grid automation - Busbar differential protection (high impedance) - Back-up protection - Motor protection - Busbar protection (voltage and frequency) - Transformer protection - 3 winding - Interconnection protection - Generator protection - Power management/Load shedding - Modbus Communication Manual - REX640 Protection and control - PCL4 - IEC - ANSI - 16.02.2023

REX640 Modbus Communication Protocol Manual

This protection relay is designed to operate with a wide range of different Modbus clients and servers. The Modbus memory map shows the protection relay's internal process data in a simple I/O map which is mainly aimed at PLC clients and other process automation devices. Time-tagged, chronological event lists and fault records can be read over the Modbus interface. This data is more suitable for SCADA Modbus clients.

The Modbus standard defines four main memory areas for mapping protection relay's process data. Due to its open nature, the Modbus standard does not define exactly what type of data should be mapped to each memory area. The Modbus mapping approach of the protection relay ensures that the same process data are readable from as many Modbus memory areas as possible. The users may then choose the memory areas that are most suitable for their Modbus client systems.